U.S. patent application number 13/093079 was filed with the patent office on 2011-09-01 for system and method of self-adjusting screen clamp.
This patent application is currently assigned to CPI Wirecloth & Screens, Inc.. Invention is credited to Ari M. Hukki.
Application Number | 20110210058 13/093079 |
Document ID | / |
Family ID | 44504739 |
Filed Date | 2011-09-01 |
United States Patent
Application |
20110210058 |
Kind Code |
A1 |
Hukki; Ari M. |
September 1, 2011 |
SYSTEM AND METHOD OF SELF-ADJUSTING SCREEN CLAMP
Abstract
A system and method allow for the installation and removal of
curved screen elements from a shaker table. Pneumatic cylinders are
used to move hold down bars either up to allow for screen elements
to be installed or removed from the screen bed section assembly, or
down to clamp screen elements into the screen bed section assembly
of a shaker so that the screen elements will not move during shaker
operations. Each curved screen element may have a different radius.
Self-adjusting hold down bars compensate for adjacent screen
elements having edges that are parallel but at different
elevations. The self-adjusting hold down bars also compensate for
adjacent screen elements having edges that are not parallel.
Inventors: |
Hukki; Ari M.; (Boynton
Beach, FL) |
Assignee: |
CPI Wirecloth & Screens,
Inc.
Pearland
TX
|
Family ID: |
44504739 |
Appl. No.: |
13/093079 |
Filed: |
April 25, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12772859 |
May 3, 2010 |
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13093079 |
|
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61215092 |
May 1, 2009 |
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Current U.S.
Class: |
210/232 ;
29/428 |
Current CPC
Class: |
B07B 1/46 20130101; Y10T
29/49826 20150115; B07B 2230/01 20130101; B07B 1/4654 20130101;
B07B 1/48 20130101 |
Class at
Publication: |
210/232 ;
29/428 |
International
Class: |
B01D 35/28 20060101
B01D035/28; B23P 17/04 20060101 B23P017/04 |
Claims
1. A system for curved screen elements in a mechanical shaker,
comprising: a first curved screen element having a first screen
element trough between two first screen element edges; a second
curved screen element having a second screen element trough between
two second screen element edges; a screen bed that houses a
pneumatic control device; a carrier frame resting on said screen
bed, wherein said carrier frame comprises a first curved support
having a first support valley between a first peak and a second
peak, and a second curved support having a second support valley
between said second peak and a third peak; a first hold down bar
slidingly disposed through said carrier frame at said second peak
of said carrier frame that is configured to be moved vertically by
said pneumatic control device between a first position that does
not resist the sliding movement of said screen elements into or
away from said carrier frame, and a second position that resists
movement of said screen elements from said carrier frame; a second
hold down bar slidingly disposed through said carrier frame at said
third peak of said carrier frame that is configured to be moved
vertically by said pneumatic control device; and a carrier frame
mounting bracket assembly positioned between said screen bed and
said carrier frame, wherein said carrier frame mounting bracket
assembly is connected to said hold down bars and said pneumatic
control device; wherein said first screen element trough is
disposed over said carrier frame first support valley with one of
said first screen element edges positioned adjacent to said second
peak of said carrier frame; wherein said second screen element
trough is disposed over said carrier frame second support valley
with one of said second screen element edges positioned adjacent to
said second peak of said carrier frame; wherein a first ledge of
said first hold down bar is configured to contact said first screen
element edge adjacent to said second peak of said carrier frame
when said first hold down bar is in said second position; wherein a
second ledge of said first hold down bar is configured to contact
said second screen element edge adjacent to said second peak of
said carrier frame when said first hold down bar is in said second
position; and wherein said first hold down bar is configured to be
adjusted by said first screen element and said second screen
element when said first hold down bar is in said second position so
as to allow said first ledge to move relative to said second
ledge.
2. The system of claim 1, wherein first hold down bar and said
second hold down bar are connected to each other with a tube
bracket, and wherein said tube bracket is attached to said carrier
frame mounting bracket assembly.
3. The system of claim 1, wherein said first ledge and second ledge
are configured to be positioned offset to each other and parallel
with each other when said first hold down bar is in said second
position.
4. The system of claim 1, wherein said first hold down bar is
configured to be self-adjusting so as to allow said first ledge to
be at a different elevation than said second ledge when said first
hold down bar is in said second position.
5. The system of claim 1, wherein said first ledge and second ledge
are positioned not parallel with each other when said first hold
down bar is in said second position.
6. The system of claim 1, wherein each of said hold down bars
comprises a first metal plate connected with a second metal plate,
and wherein said first plate has said first ledge and said second
plate has said second ledge.
7. The system of claim 6, wherein said first and second metal
plates are connected with a bolt bracket comprising a bolt bracket
first bolt and a bolt bracket second bolt.
8. The system of claim 7, wherein said bolt bracket first bolt is
disposed through a first opening in said first metal plate and a
first opening in said second metal plate, wherein said bolt bracket
second bolt is disposed through a second opening in said first
metal plate and a second opening in said second metal plate,
wherein said first metal plate first opening is smaller than said
second metal plate first opening, and wherein said first metal
plate second opening is larger than said second metal plate second
opening.
9. The system of claim 1, wherein said first screen element edges
and said second screen element edges are parallel; and wherein said
first screen element edge adjacent to said second peak has an
elevation that is different than said second screen element edge at
said second peak.
10. The system of claim 1, wherein said first screen element edges
and said second screen element edges are not parallel.
11. A method for curved screen elements in a mechanical shaker,
comprising: resting a carrier frame on a screen bed; positioning a
carrier frame mounting bracket assembly between said screen bed and
said carrier frame, wherein said carrier frame mounting bracket
assembly is connected to a plurality of hold down bars and a
pneumatic control device; sliding a first curved screen element
having a first screen element trough over a first curved support of
said carrier frame, wherein said first curved support has a first
valley between a first peak and a second peak, and wherein said
first screen element trough is between two first screen element
edges; positioning one of said first screen element edges adjacent
to said second peak of said carrier frame; sliding a second curved
screen element having a second screen element trough over a second
curved support of a carrier frame, wherein said second curved
support has a second support valley between said second peak and a
third peak, and wherein said second screen element trough is
between two second screen element edges; positioning one of said
second screen element edges positioned adjacent to said second peak
of said carrier frame; moving a first hold down bar downward with
said pneumatic control device, wherein said first hold down bar is
slidingly disposed through said carrier frame at said second peak
of said carrier frame; moving a second hold down bar downward with
said pneumatic control device, wherein said second hold down bar is
slidingly disposed through said carrier frame at said third peak of
said carrier frame, and wherein said first and second hold down
bars are connected together; holding said first screen element
against said carrier frame with a first ledge of said first hold
down bar; holding said second screen element against said carrier
frame with a second ledge of said first hold down bar; and
adjusting said first ledge and said second ledge by said first
screen element and said second screen element to account for a
difference between said first screen element and said second screen
element during said step of moving said first hold down bar
downward.
12. The method of claim 11, wherein said edges of said first and
second screen elements adjacent to said second peak are at
different elevations.
13. The method of claim 11, wherein said first ledge and said
second ledge are parallel.
14. The method of claim 11, wherein said first ledge and said
second ledge are not parallel.
15. The method of claim 11, further comprising the steps of: moving
said first hold down bar upward with said pneumatic control device;
and sliding said first curved screen element away from said carrier
frame.
16. The method of claim 11, wherein said first hold down bar
comprises a first metal plate connected with a second metal plate
with a bolt bracket, and further comprising the step of:
self-adjusting said first ledge and said second ledge with said
bolt bracket during said step of moving said first hold down bar
downward.
17. The method of claim 16, wherein said bolt bracket comprises a
first bolt and a second bolt, and further comprising the steps of:
moving said first bolt through a first opening in said first metal
plate and a first opening in said second metal plate; and moving
said second bolt through a second opening in said first metal plate
and a second opening in said second metal plate; wherein said first
metal plate first opening is smaller than said second metal plate
first opening, and wherein said first metal plate second opening is
larger than said second metal plate second opening.
18. A apparatus for curved screen elements in a mechanical shaker,
comprising: a screen bed that houses a pneumatic control device; a
carrier frame resting on said screen bed, wherein said carrier
frame comprises a first curved support having a first support
valley between a first peak and a second peak, and a second curved
support having a second support valley between said second peak and
a third peak; and a hold down bar configured to be moved vertically
by said pneumatic control device, wherein said first hold down bar
is slidingly disposed through said carrier frame at said second
peak of said carrier frame; wherein said hold down bar is
configured to hold a first curved screen element against said
carrier frame with a first ledge and to hold a second curved screen
element against said carrier frame with a second ledge when said
hold down bar is in a downward position; and wherein said first
ledge and said second ledge are configured to be adjusted by said
first screen element and said second screen element when said hold
down bar is in said downward position to account for a difference
between said first screen element and said second screen element
when said first screen element and said second screen element are
positioned adjacent to said second peak of said carrier frame.
19. The apparatus of claim 18, wherein said first ledge and said
second ledge are configured to be moved relative to each other by
said first screen element and said second screen element.
20. The system of claim 18, wherein said first ledge and said
second ledge are configured to be adjusted into positions not
parallel to each other.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of co-pending
U.S. application Ser. No. 12/772,859 filed on May 3, 2010, which
claims the benefit of U.S. Provisional Application No. 61/215,092
filed on May 1, 2009, both of which applications are hereby
incorporated by reference for all purposes in their entirety.
STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH OR DEVELOPMENT
[0002] N/A
NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
[0003] N/A
REFERENCE TO MICROFICHE APPENDIX
[0004] N/A
BACKGROUND OF THE INVENTION
[0005] 1. Field of the Invention
[0006] This invention relates to screens for vibratory machinery
and more particularly to shake table screening.
[0007] 2. Description of the Related Art
[0008] Shaker tables are well known to filter solids from liquids
in the oil, gas & petroleum industry. Screen elements are used
to filter the solids from the liquids; however, they must be
replaced periodically when they become clogged with solids or wear
down. Easy installation and removal of the screen elements is hard
to achieve. The typical practice is to install and remove the
screen elements manually, which can be difficult to accomplish, and
interrupts filtering operations for an extended period of time.
Thus, there is a need for a method and apparatus that allows for
the easy installation and removal of screen elements in a shake
table. Unfortunately, such a method and apparatus has not been
available to date.
BRIEF SUMMARY OF INVENTION
[0009] A system and method are provided to install and remove
multiple curved screen elements used for filtering solids from
liquids in a shaker table. The apparatus is comprised of a set of
hold down bars that are guided through a carrier frame. The carrier
frame holds multiple curved screen elements. The hold down bars are
connected to a carrier frame mounting bracket. This entire assembly
sits on a screen bed that houses pneumatic cylinders. In addition
to the carrier frame mounting bracket being connected to the hold
down bars, it is also connected to the pistons of the pneumatic
cylinder heads located in the screen bed. When the pneumatic
cylinders are actuated such that the pistons move upward, the hold
down bars are pushed upward allowing the curved screen elements to
be easily installed or removed by sliding them into or out of the
carrier frame. When the pneumatic cylinders are actuated such that
the pistons are in a downward position, the hold down bars clamp
the screen elements in place in the carrier frame, thus forming a
screen clamp. No tools are required to install or remove the curved
screen elements.
[0010] Each curved screen element may have a different radius, so
that each curved screen element resting on the carrier frame may
have an edge that is at a different elevation than the edge of an
adjacent curved screen element. The edges of the adjacent screen
elements may be parallel or not. In one embodiment, each hold down
bar is self-adjusting to compensate for the differences between the
edges of the two screen elements adjacent to the hold down bar that
are resting on the carrier frame. The hold down bar is adjusted by
the adjacent screen elements. Each self-adjusting hold down bar
includes a pair of metal plate sections each of which has a
respective opposed hold down bar ledge that is configured to
contact an edge of a curved screen element and hold the screen
element in place against the carrier frame when the hold down bar
is in the closed or downward position.
[0011] A pair of bolt brackets each have a pair of bolt bracket
bolts disposed through aligned openings in both metal plate
sections of the self-adjusting hold down bar. Each bolt bracket
bolt may extend through an opening in the first metal plate section
of the hold down bar that is a different size than the aligned
opening in the second metal plate section. A locking hex nut may be
disposed on the end of the bolt bracket bolt. The bolt bracket
allows the pair of plate sections of the hold down bar to move
relative to each other to self-adjust and accommodate curved screen
elements having edges that are parallel but at different elevations
or that are not parallel. Two self-adjusting hold down bars may be
connected with each other with two tube brackets and connected with
the carrier frame mounting bracket.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] A better understanding of the embodiments may be obtained
with the following detailed descriptions of the various disclosed
embodiments in the drawings, which are given by way of illustration
only, and thus are not limiting the invention, and wherein:
[0013] FIG. 1 is an isometric view of an assembled shaker;
[0014] FIG. 2 is an isometric exploded view of a shaker
assembly;
[0015] FIG. 3 is an isometric exploded view of a screen bed
assembly;
[0016] FIG. 4 is a cross sectional view of a closed screen bed
assembly;
[0017] FIG. 5 is across sectional view of a screen bed assembly
with hold down bars in an upward position for screen element
removal;
[0018] FIG. 6 is across sectional view of a screen bed assembly
with hold down bars in an upward position and with a screen element
moved away from the carrier frame;
[0019] FIG. 7 is an isometric exploded view of a screen element
assembly;
[0020] FIG. 8 is an isometric view of a hold down bar;
[0021] FIG. 9 is an isometric view of a carrier frame;
[0022] FIG. 10 is an isometric view of a hold down bar guide;
[0023] FIG. 11 is an isometric view of a carrier frame with screen
elements;
[0024] FIG. 12 is an isometric view of a screen carrier with screen
elements removed;
[0025] FIG. 13 is an isometric view of a screen element support
bar;
[0026] FIG. 14 is an isometric view of a screen carrier mounting
bracket;
[0027] FIG. 15 is an isometric exploded view of a portion of a
screen carrier mounting bracket;
[0028] FIG. 16 is an isometric exploded view of a clamp plate
assembly in a screen carrier mounting bracket;
[0029] FIG. 17 is an isometric view of a screen bed;
[0030] FIG. 18 is an isometric view of a portion of a screen bed
section;
[0031] FIG. 19 is an isometric view of a pneumatic cylinder;
[0032] FIG. 20 is an isometric exploded view of a plurality of
self-adjusting hold down bars, a plurality of screen elements, a
carrier frame, a screen carrier mounting bracket, a screen bed
section, and two pneumatic cylinders;
[0033] FIG. 21 is an isometric exploded view of a plurality of
self-adjusting hold down bars, a plurality of tube brackets, and a
screen carrier mounting bracket;
[0034] FIG. 22 is an isometric exploded view of a self-adjusting
hold down bar having a first metal plate section and a second metal
plate, two bolt brackets, and four hex nuts;
[0035] FIG. 23 is an isometric exploded view of two self-adjusting
hold down bars each having a first section and a second section,
four bolt brackets, two tube brackets and two tube bracket
bolts;
[0036] FIG. 24 is an elevational view of a self-adjusting hold down
bar that is compensating for two adjacent screen elements (not
shown) with edges that are parallel but at different
elevations;
[0037] FIG. 24A is a detail view of detail area 24A of FIG. 24;
[0038] FIG. 24B is a detail view of detail area 24B of FIG. 24;
[0039] FIG. 24C is an end view along line 24C-24C of FIG. 24;
[0040] FIG. 25 is an opposite side elevational view of the
self-adjusting hold down bar of FIG. 24;
[0041] FIG. 25A is a detail view of detail area 25A of FIG. 25;
[0042] FIG. 25B is a detail view of detail area 25B of FIG. 25;
[0043] FIG. 26 is an elevational view of a self-adjusting hold down
bar that is compensating for two adjacent screen elements (not
shown) with edges that are not parallel;
[0044] FIG. 26A is a detail view of detail area 26A of FIG. 26;
[0045] FIG. 26B is a detail view of detail area 26B of FIG. 26;
[0046] FIG. 26C is an end view along line 26C-26C of FIG. 26;
[0047] FIG. 27 is an opposite side elevational view of the
self-adjusting hold down bar of FIG. 26;
[0048] FIG. 27A is a detail view of detail area 27A of FIG. 27;
[0049] FIG. 27B is a detail view of detail area 27B of FIG. 27;
[0050] FIG. 28 is a cross sectional view of a screen bed assembly
with the self-adjusting hold down bars in the closed or downward
position;
[0051] FIG. 29 is a cross sectional view of a screen bed assembly
with the self-adjusting hold down bars in the open or upward
position for screen element removal; and
[0052] FIG. 30 is a cross sectional view of a screen bed assembly
with a screen element moved away from the carrier frame.
DETAILED DESCRIPTION OF THE INVENTION
[0053] A depiction of the general assembly of a shaker 1 that is
used with the apparatus and method of this invention can be seen in
FIG. 1. The shaker 1 is comprised of a shaker base assembly 6,
which provides a base in which a screen carrier assembly 10, shaker
basket assembly 163 and feed box assembly 47 sits. In general,
drilling mud is fed into the feed box assembly 47, which goes into
a shaker basket assembly 163. The shaker basket assembly 163
contains a screen carrier assembly 10, which serves as a filter for
the drilling mud. At least one motion generator 134 provides
shaking motion to the shaker basket assembly 163. Any solids in the
drilling mud are separated by the drilling mud moving through the
screen carrier assembly 10. The strained drilling mud is discharged
at the discharge port 29, and any solids removed from the drilling
mud travels forward on top of the screen carrier assembly 10 and
will be discharged over the discharge skirt 11.
[0054] Hold down bars 40 are pneumatically operated so that the
screen elements 45 can be easily installed or removed in the screen
carrier assembly 10. In order to operate the pneumatic controls, a
control panel support stand 73 is mounted to the side of the shaker
1. An electrical control panel 85 is then attached to the control
panel support stand 73. The control panel support stand 73 contains
a pneumatic control panel 74, which pneumatically controls the
operation of the screen carrier assembly 10.
[0055] FIG. 2 depicts an exploded view of a shaker 1. Multiple
screen carrier assemblies 10 comprise a screen carrier section
assembly 48, which is set inside the shaker 1. Each screen carrier
section 10 is set inside a screen deck assembly 20 within the
shaker 1, and is operated pneumatically. Each screen carrier
section 10 is ideally operated by two pneumatic cylinders 30, which
are operated at the pneumatic control panel 74.
[0056] An exploded screen bed section assembly 3 is depicted in
FIG. 3. Multiple screen bed section assemblies 3 sit one after the
other inside the shaker 1, and on top of the shaker base assembly 6
as shown in FIG. 1. In FIG. 3, a screen bed section 3 is comprised
of a screen bed 31 and an area to house one or more pneumatic
cylinders 30. The screen bed section 3 forms the base of the
assembly 3. Preferably two pneumatic cylinders 30 are connected to
each screen bed section 31. A carrier frame mounting bracket
assembly 60 is attached to the screen bed section 31 at the
pneumatic cylinder 30 locations. The carrier frame mounting bracket
assembly 60 is sandwiched between the carrier frame 50 and the
screen bed 31, with the carrier frame 50 sitting on the screen bed
31. Hold down bars 40 are inserted through the carrier frame 50 and
bolted to the carrier frame mounting bracket assembly 60. When the
hold down bars 40 are lifted to an upward position, curved screen
elements 45 can be slid in and out of the carrier frame 50. After
the screen elements 45 are placed inside the carrier frame 50, the
hold down bars 40 can be lowered to clamp the screen elements 45 in
place.
[0057] FIG. 4 shows a cross sectional view of the screen bed
assembly section 3 when the hold down bars 40 are in a closed
position. In FIG. 4, the screen bed section 31 contains pneumatic
cylinder holder cups 12, which house pneumatic cylinders 30. The
pneumatic cylinder holder cups 12 are supported and connected to
the screen bed section 31 by pneumatic cylinder holder support
brackets 16. The carrier frame mounting bracket assembly 60
attaches to the screen bed section 31 by bolting a clamp plate 21
to the piston 38 of a pneumatic cylinder 30. The carrier frame
mounting bracket assembly 60 is then bolted to the hold down bars
40, which are slid through guides 54 located between each screen
element 45 in the carrier frame 50. The carrier frame 50 sits
between the screen bed section 31 and the screen elements 45 that
are clamped down by the hold down bars 40. FIG. 4 shows that the
carrier frame front scallop plate 2 sits on the screen bed section
31, and is also locked into place by the hold down bars 40.
[0058] FIG. 5 is similar to FIG. 4, except that the hold down bar
40 is in an upward position. The hold down bar 40 is placed in an
upward position when the pneumatic cylinder piston 38 of the
pneumatic cylinder 30 is actuated and extends upward. When the hold
down bar 40 is in an upward position, the screen elements 45 can
easily be installed or removed. FIG. 6 shows the screen element 45
as it is moved either into or out of the screen bed assembly.
[0059] FIG. 7 shows a detailed view of a screen element 45. The
screen element 45 is comprised of a curved webbed filter 49,
preferably including stamped metal, which is then preferably coated
with an epoxy powder coating. A mesh screen 46, preferably made of
wire cloth, is placed on top of the filter 49, and heated in a heat
press until the mesh screen 46 is affixed to the filter 49 and
forms the individual screen elements 45.
[0060] FIG. 8 shows a detailed view of a hold down bar 40. Two
metal plates, each with its own ledge 41, are welded together to
form a hold down bar 40. The hold down ledges 41 serve to clamp the
screen elements 45 in place when the hold down bar 40 is in a
closed position.
[0061] FIG. 9 is a detailed view of a carrier frame 50. Each
carrier frame includes, for example, two carrier frame side plates
5 and two carrier frame scallop plates 2, which are welded together
to form a frame. The carrier frame 50 sits on top of the screen bed
31, and supports the screen elements 45. To better support the
screen elements 45, screen element support bars 52, preferably two,
are welded beneath each scallop in the scallop plates 2 where the
curved portion of the screen element 45 will rest. In between where
each screen element 45 will rest, a hold down bar guide 54 is
welded to the carrier frame 50. The hold down bar guide 54 provides
the location where the hold down bars 40 will move up and down
through the carrier frame 50. As discussed previously, when the
hold down bars 40 are in an upward position, screen elements 45 can
be easily installed and removed. However, when the hold down bars
40 are in a lowered position through the hold down bar guide 54,
the hold down bar ledges 41 will clamp the screen elements 45 into
the carrier frame 50.
[0062] FIG. 10 is a detailed view of the hold down bar guide 54,
which is placed between each scallop in the scallop plates 2 of the
carrier frame 50. The hold down bar guide 54 is preferably a
u-shaped piece of metal with channels cut so that the hold down
bars 40 can slip through the hold down bar guide 54 and connect to
the carrier frame mounting bracket assembly 60.
[0063] FIG. 11 depicts the carrier frame 50 when the screen
elements 45 are in place, and the hold down bars 40 are in the
closed position.
[0064] FIG. 12 shows another view of the screen bed section
assembly 3 with the screen elements 45 removed.
[0065] FIG. 13 is a detailed view of the screen element support bar
52, which sits at the bottom of each scallop in the scallop plates
2 of the carrier frame 50. The screen element support bar 52 is
preferably metal, and preferably welded to the carrier frame 50.
The use of two screen element support bars 52 is preferred to
support each screen element 45 in the carrier frame 50.
[0066] FIG. 14 is a detailed view of the screen carrier mounting
bracket 60. Two mounting bracket supports 55 are connected by two
clamp plates 21. The preferable means of connection is by bolting
the pieces together, although these pieces of the screen carrier
mounting bracket 60 could be one continuous piece or could be
connected by weld. Tube brackets 70 are affixed to a tube bracket
adaptor 57, which is in turn attached to each mounting bracket
support 55. Preferably, each tube bracket 70 and tube bracket
adaptor 57 is metal, and each is attached to the respective
component by bolting the components together. However, it is
envisioned that these components could be attached by other means
known in the art.
[0067] FIG. 15 is an exploded view of the screen carrier mounting
bracket 60 and shows the preferred embodiment of bolting tube
bracket adapters 57 to the mounting bracket support 55, and
mounting tube brackets 70 to the tube bracket adaptors 57. FIG. 16
is another exploded view of the screen carrier mounting bracket 60
that shows the preferred embodiment of bolting the clamp plates 21
to the mounting bracket support 55.
[0068] The clamp plates 21 sit on the pneumatic cylinder cup
holders 4 shown in FIG. 17. Each clamp plate 21 is bolted to the
pneumatic cylinder piston 38 which is centered inside the pneumatic
cylinder cup holder 4. The hold down bars 40 are bolted to the ends
of the tube brackets 70 of the carrier frame mounting bracket
assembly 60.
[0069] FIG. 17 shows a screen bed 35, which is comprised of front
screen bed sections 32 and side screen bed sections 33, which make
up an overall frame for the screen bed 35. FIG. 18 shows how each
pneumatic cylinder holder cup 12 is braced by pneumatic cylinder
holder support brackets 16, which are affixed to the screen bed
sections 31, preferably by weld. FIG. 19 shows a pneumatic cylinder
30, which sits inside the pneumatic cylinder holder cup 12. The
pneumatic cylinder piston 38 extends through the middle of the
pneumatic cylinder holder cup 12 and is bolted to the clamp plate
21 of the screen carrier mounting bracket assembly 60.
[0070] Turning to FIG. 20, an exploded screen bed assembly section
3A is shown with self-adjusting hold down bars 40A that are
positioned through the hold down bar guides 54 of the carrier frame
50 and attached with the carrier frame mounting bracket 60 using
tube brackets 70, as described in detail below. The screen bed 31
houses one or more pneumatic cylinders 30. The screen bed section
31 forms the base of the assembly 3A. Preferably two pneumatic
cylinders 30 are connected to each screen bed section 31. A carrier
frame mounting bracket assembly 60 is attached to the screen bed
section 31 at the pneumatic cylinder 30 locations. The carrier
frame mounting bracket assembly 60 is sandwiched between the
carrier frame 50 and the screen bed 31, with the carrier frame 50
sitting on the screen bed 31.
[0071] The self-adjusting hold down bars 40A clamp or hold the
plurality of screen elements 45 against the carrier frame 50 when
in the closed position. Each of the screen elements 45 has opposing
edges with a valley or trough between them, such as exemplary
screen element 45A with opposing edges (86A, 86B), and screen
element 45B with opposing edges (87A, 87B). Each of the two scallop
plates 2 of the carrier frame 50 have a plurality of peaks 90 and
valleys or troughs 91. The hold down bar guides 54 are disposed at
the carrier frame peaks 90. Each screen element 45 rests in one of
the carrier frame troughs 91, with each screen element edge
adjacent to one of the peaks 90. Each curved screen element 45 may
have a different radius. At a carrier frame peak 90 shared by two
adjacent screen elements 45, the edges of the two screen elements
located adjacent to the shared peak may be at different elevations
and/or may not be parallel with each other. As discussed below, the
self-adjusting hold down bars 40A accommodate this situation while
still holding the screen elements 45 against the carrier frame 50
when in the closed position.
[0072] In FIG. 21, the exemplary hold down bar assembly system 4
includes the carrier frame mounting bracket assembly 60, a
plurality of self-adjusting hold down bars 40A, and a plurality of
tube brackets 70, each of which has two bolt brackets 76 attached.
Each self-adjusting hold down bar 40A is paired with another
self-adjusting hold down bar 40A that is adjacent to it, and the
two hold down bars 40A are attached together using two tube
brackets 70, which two tube brackets 70 are attached on opposite
sides of the carrier frame mounting assembly 60.
[0073] In FIG. 22, the assembly of a single self-adjusting hold
down bar 40A is shown using two bolt brackets 76 and four locking
hex nuts 74. A single adjustable hold down bar 40A comprises two
metal plate sections (42A, 42B), each of which has a respective
opposed hold down bar ledge (41A, 41B) that is used to contact an
edge of an adjacent screen element 45 and hold the screen element
45 in place against the carrier frame 50 when the adjustable hold
down bar 40A is in the closed position. Each bolt bracket 76 has
two bolt bracket bolts 68. One bolt 68 is positioned through the
outer hole 80A of the first plate section 42A and the outer slot 78
of the second plate section 42B. The other bolt 68 is positioned
through the outer slot 78A of the first plate section 42A and the
outer hole 80 of the second plate section 42B. One locking hex nut
74 may be disposed on the end of each bolt bracket bolt 68. The
nuts 74 are not tightened against the second plate section 42B, so
as to allow the first and second plate sections (42A, 42B) to move
relative to each other. Other means of connection are also
contemplated. Each set of adjacent three openings, such as openings
(77, 78, 80) or openings (77A, 78A, 80A), are located at the base
of their respective plate section (42A, 42B). Each base is located
at the end of the respective legs 85A or 85B on the first plate
section 42A or second plate section 42B.
[0074] The three openings may be of different sizes, such as
circular for outer hole 80 and different length slots for center
slot 77 and outer slot 78, with both slots (77, 78) having lengths
greater than the diameter of the circular opening 80. Other shapes,
sizes and relationships are also contemplated. Outer slot 78A of
first plate 42A is aligned with outer hole 80 of second plate 42B.
Although not shown, tube bracket bolt 75 is positioned through the
center slots (77, 77A).
[0075] Turning to FIG. 23, an exemplary pair of self-adjusting hold
down bars 40A may be connected together using two tube brackets 70.
The opposed metal plate sections (42A, 42B) of each self-adjusting
hold down bar 40A are each connected together with two bolt
brackets 76 and four hex nuts 74. Tube bracket bolts 75 are
positioned within tube brackets 70, and each bolt 75 is positioned
through the center of the three openings at the base of the hold
down bar 40A. A locking hex nut 74 may be disposed on the end of
the tube bracket bolt 75. The center opening through which the tube
bracket bolt extends is slotted to allow each pair of plate
sections (42A, 42B) to move relative to each other. The pair of
hold down bars 40A are attached together, and the bolt brackets 70
are attached on opposite sides of the mounting bracket assembly
60.
[0076] FIGS. 24-25B show how the self-adjusting hold down bars 40A
accommodate adjacent screen elements 45 (not shown) resting on the
carrier frame 50 that at a shared peak 90 of the carrier frame 50
have screen element edges that are parallel, but at different
elevations. In FIGS. 24 and 25, the attached first plate 42A and
second plate 42B of a single adjustable hold down bar 40A have
shifted vertically relative to each other due to adjacent curved
screen elements having edges at different elevations. The adjacent
screen elements 45 have moved the first plate 42A and second plate
42B as shown. FIGS. 24A and 24B show how the two bolt brackets 76
through the hold down bar 40A have become angled from the uneven
screen elements. The angle of the two bolt brackets 76 from
horizontal is the same in FIGS. 24A and 24B since the edges of the
two different screen elements are parallel.
[0077] The angle of the two bolt brackets 76 from horizontal shown
in FIGS. 24A and 24B is shown for the maximum parallel offset 79 of
the first plate 42A with the second plate 42B, which is shown in
FIG. 24C. This corresponds with the maximum parallel offset of
edges of adjacent parallel screen elements 45. The ledge 41A of
first plate section 42A is at a first elevation and the ledge 41B
of second plate section 42B is at a second elevation. The first
elevation is different than the second elevation, and both
elevations remain constant since the edges of the adjacent screen
elements 45 are parallel. If the difference in elevation of the
adjacent screen elements is smaller, then a smaller angle from
horizontal for the bolt brackets 76 will be created for a smaller
parallel offset 79. There will be no angle if the adjacent screen
element edges are at the same elevation and no offset 79
required.
[0078] In FIGS. 25A and 25B, the bolt bracket bolts 68 extend
through the second plate 42B of the hold down bar 40A. In FIG. 25B,
it can be seen that the outside circular opening 80A of the first
plate 42A is aligned with the outside slot 78 of the second plate
42B, which, along with the alignment of the other openings (78A,
80), allows for the bolt bracket 76 to self-adjust based upon the
condition of the adjacent screen elements 45 (not shown). Although
not shown, tube bracket bolt 75 is positioned through the center
slots (77, 77A) for attachment of the hold down bar 40A with
another hold down bar and the carrier frame mounting bracket
assembly 60 using the tube bracket 70. The locking hex nut 74 on
the end of the tube bracket bolt 75 is not tightened against the
hold down bar 40A, and the center slots (77, 77A) allow the pair of
metal plate sections (42A, 42B) to move relative to each other.
[0079] In one embodiment of a method, the screen elements 45 may be
positioned on the troughs 91 of the carrier frame 50 with the
adjustable hold down bars 40A in the upward position. The hold down
bars 40A may then be lowered to the closed position. If two
adjacent screen elements 45 have edges at a shared peak 90 of the
carrier frame 50 that are parallel but at different elevations or
heights, then the bolt brackets 76 will self-adjust to change the
elevations of the hold down bar ledges (41A, 41B), similar to as
shown in FIGS. 24-25B, to account for the difference in elevations.
Each self-adjusting hold down bar will hold the two screen elements
adjacent to it against the carrier frame. Other methods are also
contemplated.
[0080] FIGS. 26-27B show how the self-adjusting hold down bars 40A
accommodate adjacent screen elements 45 (not shown) resting on the
carrier frame 50 that have screen element edges at a shared peak 90
of the carrier frame 50 that are not parallel. In FIGS. 26 and 27,
the attached first plate 42A and second plate 42B of a single
self-adjusting hold down bar 40A have shifted relative to each
other due to adjacent curved screen elements having edges that are
not parallel. The adjacent screen elements have moved the first and
second plates (42A, 42B) as shown. FIGS. 26A and 26B show how the
two bolt brackets 76 through the hold down bar 40A have become
angled. The angle of the two bolt brackets 76 from horizontal is
different in FIGS. 26A and 26B since the edges of the two different
screen elements (not shown) are not parallel.
[0081] The difference in angle of the two bolt brackets 76 from
horizontal shown in FIGS. 26A and 26B is for the maximum
non-parallel offset 81 of the first plate 42A with the second plate
42B, which is shown in FIG. 26C. This corresponds with the maximum
non-parallel offset of the edges of two adjacent screen elements.
The ledge 41A of first plate section 42A is at a first elevation
and the ledge 41B of second plate section 42B is at a second
elevation. The first elevation is different than the second
elevation, and both elevations are not necessarily constant since
the edges of the adjacent screen elements 45 are not parallel. The
bolt brackets 76 move independently to other angles and/or
orientations for different non-parallel offset amounts.
[0082] In FIGS. 27A and 27B, the bolt bracket bolts 68 extend
through the second plate 42B of the self-adjusting hold down bar
40A. In FIG. 27B, it can be seen that the outside circular opening
80A of the first plate 42A is aligned with the outside slot 78 of
the second plate 42B, which, along with the alignment of the other
openings (78A, 80), allows for the bolt bracket 76 to self-adjust
based upon the condition of the adjacent screen elements 45 (not
shown). Although not shown, tube bracket bolt 75 is positioned
through the center slots (77, 77A) for attachment of the hold down
bar 40A with another hold down bar and the carrier frame mounting
bracket assembly 60 using the tube bracket 70.
[0083] In one embodiment of a method, the screen elements 45 may be
positioned on the troughs 91 of the carrier frame 50 with the
adjustable hold down bars 40A in the upward position. The hold down
bars 40A may then be lowered to the closed position. If two
adjacent screen elements 45 have edges at a shared peak 90 of the
carrier frame 50 that are not parallel, then the bolt brackets 76
will self-adjust to change the elevations of the hold down bar
ledges (41A, 41B), similar to as shown in FIGS. 26-27B, to account
for the differences, while still holding the screen elements
against the carrier frame 50. Other methods are also
contemplated.
[0084] FIG. 28 shows a cross sectional view of the screen bed
assembly section 3A when the hold down bars 40A are in a closed
position. The screen bed section 31 contains pneumatic cylinder
holder cups 12, which house pneumatic cylinders 30. The pneumatic
cylinder holder cups 12 are supported and connected to the screen
bed section 31 by pneumatic cylinder holder support brackets 16.
The carrier frame mounting bracket assembly 60 attaches to the
screen bed section 31 by bolting a clamp plate 21 to the piston 38
of a pneumatic cylinder 30. The carrier frame mounting bracket
assembly 60 is then bolted to the hold down bars 40A, which are
slid through guides 54 located between each screen element 45 in
the carrier frame 50. The carrier frame 50 sits between the screen
bed section 31 and the screen elements 45 that are clamped down by
the hold down bars 40A. The carrier frame front scallop plate 2
sits on the screen bed section 31, and is also locked into place by
the hold down bars 40A.
[0085] FIG. 29 is similar to FIG. 28, except that the hold down bar
40A is in an upward position. The hold down bar 40A is placed in an
upward position when the pneumatic cylinder piston 38 of the
pneumatic cylinder 30 is actuated and extends upward. When the hold
down bar 40A is in an upward position, the screen elements 45 can
easily be installed or removed. FIG. 30 shows the screen element 45
as it is moved either into or out of the screen bed assembly.
[0086] The foregoing disclosure and description of the invention is
illustrative and explanatory thereof. Various changes in the
details of the illustrated construction can be made within the
scope of the present claims without departing from the true spirit
of the invention. The invention should only be limited by the
following claims and their legal equivalents.
* * * * *